Title: Spectroscopically resolved resonant interatomic Coulombic decay in photoexcited large He nanodroplets
Authors: L. Ben Ltaief , K. Sishodia, R. Richter, B. Bastian , J. D. Asmussen, S. Mandal, N. Pal, C. Medina, S. R. Krishnan, K. von Haeften, and M. Mudrich
DOI: https://doi.org/10.1103/PhysRevResearch.6.013019
Date: 01/08/2024
Working Group: WG4
Grant Period: 1st GP 2022-2023
Grant Period Goal (number): GPG2, GOG4
Covered deliverables from the MoU (number): 4.2.2
Countries involved: Denmark, Italy, India, Germany
Number of female/young/ITC coauthors: 7
Abstract: Interatomic Coulombic decay (ICD) processes play a crucial role in weakly bound complexes exposed to
intense or high-energy radiation. Using large helium nanodroplets, we demonstrate that ICD is efficient even
when the droplets are irradiated by weak synchrotron radiation at relatively low photon energies. Below the
ionization threshold, resonant excitation of multiple centers efficiently induces resonant ICD as previously
observed for intense pulses [A. C. LaForge et al., Phys. Rev. X 11, 021011 (2021)]. More surprisingly, we
observe ICD even above the ionization threshold due to recombination of photoelectrons and ions into excited
states which subsequently decay by ICD. This demonstrates the importance of secondary processes, in particular
electron scattering and recombination, in inducing ICD in extended condensed phase systems. High-resolution
ICD electron spectra in combination with coincidence imaging of electrons and ions reveal the relaxation
dynamics of highly excited and ionized weakly bound nanosystems.
